Here, at two hundred feet, the sun streamed feebly. A large, silk-skinned sea mammal rolled idly by, inspecting the craft with a kind of half-interest, as if it had half expected to find something of this kind round about here, and then it slid on up and away towards the rippling light.

The craft waited here for a minute or two, taking readings, and then descended another hundred feet. At this depth it was becoming seriously dark. After a moment or two the internal lights of the craft shut down, and in the second or so that passed before the main external beams suddenly stabbed out, the only visible light came from a small, hazily illuminated pink sign that read, THE BEEBLEBROX SALVAGE AND REALLY WILD STUFF CORPORATION.

The huge beams switched downwards, catching a vast shoal of silver fish, which swivelled away in silent panic.

In the dim control room that extended in a broad bow from the craft’s blunt prow, four heads were gathered round a computer display that was analysing the very, very faint and intermittent signals that were emanating from deep on the seabed.

“That’s it,” said the owner of one of the heads finally.

“Can we be quite sure?” said the owner of another of the heads.

“One hundred per cent positive,” replied the owner of the first head.

“You’re one hundred per cent positive that the ship which is crashed on the bottom of this ocean is the ship which you said you were one hundred per cent positive could one hundred per cent positively never crash?” said the owner of the two remaining heads. “Hey”—he put up two of his hands—“I’m only asking.”

The two officials from the Safety and Civil Reassurance Administration responded to this with a very cold stare, but the man with the odd, or rather the even number of heads, missed it. He flung himself back on the pilot couch, opened a couple of beers—one for himself and the other also for himself—stuck his feet on the console, and said “Hey, baby,” through the ultra-glass at a passing fish.

“Mr. Beeblebrox . . .” began the shorter and less reassuring of the two officials in a low voice.

“Yup?” said Zaphod, rapping a suddenly empty can down on some of the more sensitive instruments. “You ready to dive? Let’s go.”

“Mr. Beeblebrox, let us make one thing perfectly clear . . .”

“Yeah, let’s,” said Zaphod. “How about this for a start. Why don’t you just tell me what’s really on this ship.”

“We have told you,” said the official. “By-products.”

Zaphod exchanged weary glances with himself.

“By-products,” he said. “By-products of what?”

“Processes,” said the official.

“What processes?”

“Processes that are perfectly safe.”